As part of the Comprehensive School Physical Activity Program, we investigated how early morning physical activity affects elementary school students' physical fitness and sociality. Seventy-five boys in 6th grade of one elementary school located in G Metropolitan City, Korea comprised the experimental group that participated in early morning physical activity for 6 months. The control group did not perform said activities. Experimental design for this study adopted pre- and post-measurement and comparison methods between groups. Collected data were analyzed with analyses of covariance and Bonferroni post-hoc tests. The experimental group showed significant differences in the improvement of cardiorespiratory endurance and muscle strength among the sub-elements of physical fitness compared to controls. They also showed significant differences in the development of sociability, activity, autonomy, stability, and dominance among the sub-factors of sociality compared to controls. We elucidated the importance of early morning physical activity performed before school, which has implications for schools' physical education programs.